In C++, we always expected to invoke the dtor for moved-from objects.
This is not the case for swift. Fortunately, @inCxx calling convention
is already expressing that the caller supposed to destroy the object.
This fixes the missing dtor calls when calling C++ functions taking
rvalue references. Fixes#77894.
rdar://140786022
Add a test case that checks the behaviour introduced during the refactor
of `importFunctionParameterList` and `importMethodParamsAndReturnType`.
The test checks that both Obj-C++ methods and C++ functions treat `const
T&` parameters in the same way.
The C++ interop modules require C++ support. Explicitly require C++ as
a feature when building these modules. This has no impact on the
changes as all the tests enable C++ already.
